Behavior Research Methods, Instruments, & Computers 1999,31 (I). 81-85
The generation effect: Software demonstrating the phenomenon WILLIAM LANGSTON Middle Tennessee State University, Murfreesboro, Tennessee The generation effect occurs when people demonstrate better memory for material that they have generated than for material that they have merely read. The software described here allows students to participate in replications of generation effect experiments. The program can be used with its default settings to present simple experiments. I have used this feature in research methods courses to provide data for writing research reports. The program can also be modified to allow students to design and conduct their own variations of generation effect experiments.
Siamecka and Graf (1978) presented five experiments demonstrating that memory for self-generated material is better than memory for material that is merely read. They dubbed this phenomenon the generation effect. This effect has since received a lot of attention (Begg & Snider, 1987; Begg, Vinski, Frankovich, & Holgate, 1991; Burns, 1990, 1992; Gardiner, Smith, Richardson, Burrows, & Williams, 1985; Glisky & Rabinowitz, 1985; Greenwald & Johnson, 1989; Hirshman & Bjork, 1988; Johns & Swanson, 1988; McDaniel, Waddill, & Einstein, 1988; McElroy & Siamecka, 1982; Nairne, Pusen, & Widner, 1985; Payne, Neely, & Burns, 1986; Schmidt & Cherry, 1989; Siamecka & Fevreiski, 1983; Slamecka & Katsaiti, 1987; Watkins & Sechler, 1988). This report describes software that allows students to participate in generation effect experiments. Siamecka and Graf (1978) presented lists of word pairs to their participants. Each pair was produced using some rule (e.g., a rhyming pair would be rave-cave). For the read condition, participants read this list of word pairs. They were also told the rule that related the words in each pair. For the generate condition, participants were told the rule, and then they saw the stimulus word and the first letter of the response (rave-c). The participant's task was to complete the response. After the list was presented, participants were given a memory test. Siamecka and Graf (1978) found the generation effect to be a robust phenomenon. They found significant effects with recognition, free recall, and cued recall memory tests. They found the effect when the read and generate tasks were presented within participants and when the tasks were presented between participants. They found the effect for intentional and incidental memory conditions. The only limitations were on the effect reported by
I thank Steve Schmidt for a careful reading ofthe manuscript and for testing the software. Address correspondence to W. Langston, Department of Psychology, MTSU Box X-174, 130I East Main Street, Murfreesboro, TN 37132 (e-mail:
[email protected]).
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Siamecka and Graf for recognition memory and cued recall for the stimuli. Since Siamecka and Graf, the robustness of the effect has been qualified by a number of observations. McElroy and Siamecka (1982) found that there was no generation effect for nonwords (see also Nairne et al., 1985; Payne et al., 1986; but see Johns & Swanson, 1988, for a generation effect with nonwords). Nairne et al. (1985) found no generation effect with low-frequency words. Siamecka and Katsaiti (1987) found no generation effect for bilingual (Greek-English) word pairs. They also found no generation effect for lists presented between participants (see also Begg & Snider, 1987). Schmidt and Cherry (1989) found that reading is superior to generating when participants recall both members of the pair. Begg et al. (1991) found a reduced or reversed effect when participants were instructed to imagine the referent of the response. Burns (1992) found that reading is superior to generating with slow presentation rates and a free recall task. Much of the research on the generation effect has been conducted to distinguish between various theoretical accounts of the effect. The main three competing explanations of the generation effect are as follows: (1) Generating enhances information about the relation between the stimulus term and the response, (2) generating enhances information about the generated word itself, and (3) generating produces a combination of both types of enhancement (a multifactor account) (Burns, 1990; Hirshman & Bjork, 1988; see also Siamecka & Katsaiti, 1987, for other possible explanations). McDaniel et al. (1988) added a third component to the multi factor account: Generating enhances encoding of the list structure. Testing between these accounts involves manipulating some variable that should cause the generation effect to obtain or not obtain and looking for the effect. In Table I, I present a list of experiments investigating the generation effect. For each experiment, I outline the basic design and present a simplified version of the results. Inclusion in the table was generally restricted to experiments using list-learning paradigms, since these are
Copyright 1999 Psychonomic Society, Inc.
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Table 1 Representative Experiments, Basic Design, and Direction ofthe Generation Effect Representative Experiments Siamecka & Graf (1978) I
2
3 4 5
Slamecka & Fevreiski (1983) I Glisky & Rabinowitz (1985) I Gardiner et al. (1985)
Johns & Swanson (1988) I Watkins & Sechler (1988) I
2
Greenwald & Johnson (1989) I
McElroy & Siamecka (1982) I Nairne et al. (1985) I
3
Payne et al. (1986) I Siamecka & Katsaiti (1987) I 3
Schmidt & Cherry (1989) I Begg et al. (1991) I
Basic Design Generate versus read between participants; five rules (associate, category, opposite, synonym, rhyme); recognition memory test. Self-paced presentation and experimenter-paced presentation (4 sec per item). Generate versus read within participants. Intentional and incidental learners. Recognition test for stimuli. Recognition test for responses. Three rules (synonym, opposite, rhyme); free recall. Cued recall for stimuli. Cued recall for responses. Extensions of the Effect Likelihood of generation on the effect; low information generation (trivial-v) versus high information (trivial-vi-l); free recall. Successful and unsuccessful generation. Single word task. Read a word or complete a fragment; incidental learning; recognition memory. Effect of generation difficulty on recall; manipulate difficulty by removing zero through four letters from five letter words. Generation effect for nonwords; reveal entire nonword at the end of generation. Words and nonwords; recall and recognition tests. Incidental memory task. Participants instructed to memorize pictures; generate and read stimuli presented as distractor material. Incidental and intentional learners. Antonym task, test memory for stimuli. Cued recall for stimuli and free recall for stimuli. Recognition for stimuli. Limitations of the Effect Generation effect for nonwords; recognition memory. Timed and self-paced presentation for words. Timed and self-paced presentation for nonwords. Generation effect for nonwords; frequency manipulation. Participants told nonwords are obscure words or nonwords; free recall. Nonwords and low-frequency words (s l/miltion); recognition. Medium-frequency (25-40/million) and high-frequency (> I DO/million) words; recognition. Relationship between stimulus and response. Word stimulus-word response and nonword stimulus-word response. Word stimulus-nonword response and nonword stimulus-nonword response. Effect of bilingual word pairs; between- versus within-participants designs. Generate versus read within participants; English-English word pairs. Generate versus read within participants; Greek-English word pairs. Generate versus read within participants; English-English word pairs. Generate versus read between participants; English-English word pairs. Reversals of the Effect Recall of both members of a word pair; generation task is easy (1.3 letters omitted) versus hard (2.6 letters omitted). Easy and hard generation, free recall and cued recall. Manipulate strategy used during reading and generating. Pronounce response (generated or read). Imagine referent of response (generated or read).
Burns (1992) IA IS IC
Slow (7 sec/item) versus fast (14 sec/item) presentation. Recognition memory (5 AFC, 2-week delay); fast and slow rates. Cued recall; fast and slow rates. Free recall; slow rate. Free recall; fast rate.
Effect
Generate> Read Generate> Read No effect Generate> Read Generate> Read No effect Generate> Read
Generate> Read Generate> Read Generate> Read (more letters removed leads to better recall) Generate> Read Generate> Read Generate> Read (bigger for incidental) Generate> Read No effect
Generate> Read No effect No effect No effect Generate> Read
Generate> Read No effect Generate> Read No effect Generate> Read No effect
Read> Generate Generate> Read (not always reliable) Read> Generate or No effect Generate> Read Generate> Read Read> Generate No effect
GENERATION EFFECT DEMONSTRATION
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the sorts of experiments that the software was designed to present. The summaries presented in the table are not intended to be exhaustive summaries of the articles described. The focus is on manipulations that affect the presence of the effect. The implications for theoretical accounts of the generation effect have not been included.
ate tasks between or within participants). For parameters with theoretical implications, citations have been provided that demonstrate the use of the parameter. A description of the possible settings of each parameter has also been included. The parameters are arranged according to their location in the program.
THE SOFTWARE
USING THE SOFTWARE
My goal in developing the software was to provide a Students should be assigned a participant number and first experiment to use in my Research Methods courses. a condi tion (read or generate) before carrying out the exI have used the experiment as the foundation for the first periment. It is possible to hide all of the files from the lab report several times, and I have found that the exer- students. All they need to see is a parameter file called cise of writing a generation effect paper transfers well to "Double-click me." Launching this starts the program. the writing offuture papers in the class. This experiment Students can then enter their participant number and is ideal for research methods applications for a number choose read or generate. Help is available in the software of reasons. First, the effect is robust. It is useful for the for the basic experiment set-up. first experiment to come out as expected. Second, it is A little more instruction is required in order to get stusimple to conduct. Third, the motivation for the research dents to save the data. The program offers the save opis accessible to undergraduates with limited knowledge tion immediately after the experiment. I usually instruct of psychology. students to save their data in a special folder for the class. The software can be used in its default mode, or it can Non-Macintosh users sometimes have trouble with this. be modified to present a wide range of experiments (repThe data file is a text file which contains the memory lication of most of the experiments in Table I is possible). results. It also contains all of the parameter settings and The default experiment is a simple demonstration of the the word lists. Lists are shown in the order presented and generation effect. Participants may read or generate a re- categorized by rule. The program will not automatically sponse list with 24 word pairs: 8 pairs in each of three compute serial position curves or other sophisticated rules. In the default mode, the reading and generating memory measures. However, all of the information retasks are presented between participants. The rules are the quired for these computations is available in the data file. opposite (e.g., up-down), category (e.g., pen-pencil), Parameter sets that replicate the experiments in Slaand rhyme (e.g., grape-ape) rules from Slamecka and mecka and Graf (1978) have been included with the softGraf (1978). There are also three practice trials for each ware (with the exception that only three rules are used). rule. In the default mode, generating is self-paced, and The program's flexibility also allows instructors to reading is at a rate of 4 sec per item. The default memory demonstrate other list-learning memory experiments. As task is free recall. After (in experimental session, partic- an example, parameter sets that allow partial replication ipants may save their data as a text file. If the program's of the experiments in Glanzer and Cunitz (1966) (invesfolder is on the Desktop, the default experiment will run tigating transfer from short-term memory to long-term automatically when the program is launched. This ver- memory) and Bjork and Whitten's (1974) Experiment I sion of the experiment is the one that I have used in my (investigating long-term recency) have been included. methods classes. The software may also be modified by using a set of CONCLUSION parameters to implement variations on the basic experiment. These parameter settings can be saved, and the proI have found that the generation effect makes a nice first gram can be launched by double-clicking on the parameter experiment for use in Research Methods courses. The effile. When launched from a file, the parameter settings fect is robust (in four semesters of using the experiment, replace the default settings. The word lists can also be generate participants have demonstrated better memory modified, further increasing the program's flexibility. than read participants every time). The number of poTemplate word files for between-participants and within- tential variations is enormous, and the literature is acparticipants lists are included with the experiment. These cessible to undergraduates. files contain detailed instructions on list construction. The Availability. I developed the software using Think Paspath to a word list can be stored with a parameter set, au- cal (1991). The software will run on any Macintosh with tomating the process of carrying out novel experiments. System 7 or higher as its operating system. The software In Table 2, I present a list of the program parameters has been tested on various Power Macintoshes (one runthat users may set. Some of these parameters were included ning System 8), and some earlier models. The software in the program for practical purposes (e.g., to hide in- is available on my web site, www.mtsvedu/-wlangsto. structions). Others have implications for theoretical ac- The software can also be obtained by sending a disk to counts of the effect (e.g., presenting the read and gener- the author.
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Table 2 Program Parameters, Representative Experiments, and Possible Settings Program Parameter Self- versus experimenter-paced presentation. Hide cues (stimuli). Generate from first letter versus fragment.
Rules are blocked or in random order.
Repeat the entire list N times. Repeat each item N times. Delay N seconds after each item. Delay N seconds after list presentation.
Representative Experiments
Possible Settings
Presentation Parameters Siamecka & Graf (1978) Generate and read tasks can be either self- or experimenter-paced. Allows presentation of word lists for additional types of memory experiments. Siamecka & Fevreiski (1983) First letter presents pairs in the format "grape-a." Fragment presents pairs in the format "grape-a-e"; the number ofletters removed can be set from zero to N. Siamecka & Graf (1978) Blocking rules presents all words within a rule in adjacent list positions. Random presents them in random order. A third setting allows presentation in the same order as the word list file. Siamecka & Graf (1978) The list can be repeated up to five times. Each item can be repeated up to five times in a row. A filled (counting backward) or unfilled delay can be presented after each item for N seconds. A filled (counting backward) delay can be presented Siamecka & Graf (1978) for N seconds after the list. Test Parameters
Memory task is free recall, cued recall, or recognition. Remember stimuli versus responses.
Present read/generate tasks within participants. Hide instructions. Hide practice. Intentional versus incidental instructions.
Burns (1992)
One of the three memory tasks can be used.
Greenwald & Johnson (1989)
The memory task can be based on the stimulus list or the response list.
General Parameters Slamecka & Katsaiti (1987)
Watkins & Sechler (1988)
Loose scoring (whatever is generated is "correct") versus strict scoring.
Enable mouse-click escapes.
Attach word file to parameter set.
REFERENCES BEGG, I., & SNIDER, A. (1987). The generation effect: Evidence for generalized inhibition. Journal of Experimental Psychology: Learning, Memory, & Cognition, 13, 553-563. BEGG, I., VINSKI, E., FRANKOVICH, L., & HOLGATE, B. (1991). Generating makes words memorable, but so does effective reading. Memory & Cognition, 19,487-497. BJORK, R. A., & WHITTEN, W. B. (1974), Recency-sensitive retrieval processes in long-term free recall. Cognitive Psychology, 6,173-189. BURNS, D. J. (1990). The generation effect: A test between single- and multi-factor theories. Journal ofExperimental Psychology: Learning, Memory, & Cognition, 16,1060-1067. BURNS, D. J. (1992). The consequences of generation. Journal ofMemory & Language, 31, 615-633. GARDINER, J. M., SMITH, H. E. RICHARDSON, C. J., BURROWS, M. v: & WILLIAMS, S. D. (1985). The generation effect: Continuity between generation and reading. American Journal ofPsychology, 98, 373-378.
c.
The read/generate tasks can be within participants or between participants. The automatic instructions can be suppressed if experimenters want to substitute custom instructions. Hiding practice allows the use of custom practice trials. Intentional memory instructions describe the memory task and present a practice memory test. Incidental instructions do not mention memory and suppress the practice memory test. For loose scoring, the participant's generated list will be used to score memory. For strict scoring, only responses consistent with the word list file will be scored as correct. Typing "quit" at any point where a typed response is expected will always escape from the program. Enabling mouse clicks will cause an escape if the mouse button is depressed when the program is presenting timed information (such as the read task). Attaching a custom word file to a parameter set allows experimenters to change the default word file.
GLANZER, M., & CUNITZ, A. R. (1966). Two storage mechanisms in free recall. Journal of VerbalLearning & VerbalBehavior.S, 351-360. GUSKY, E. L., & RABINOWITZ, J. C. (1985). Enhancing the generation effect through repetition of operations. Journal ofExperimental Psychology: Learning, Memory, & Cognition, 11, 193-205. GREENWALD, A. G., & JOHNSON, M. M. S. (1989). The generation effect extended: Memory enhancement for generation cues. Memory & Cognition, 17,673-681. HIRSHMAN, E., & BJORK, R. A. (1988). The generation effect: Support for a two-factor theory. Journal ofExperimental Psychology: Learning, Memory, & Cognition, 14,484-494. JOHNS, E. J., & SWANSON, L. G. (1988). The generation effect with nonwords. Journal of Experimental Psychology: Learning, Memory, & Cognition, 14, 180-190. McDANIEL, M. A., WADDILL, P. J., & EINSTEIN, G. O. (1988). A contextual account of the generation effect: A three-factor theory. Journal ofMemory & Language, 27, 521-536. McELROY, M. A., & SLAMECKA, N. J. (1982). Memorial consequences
GENERATION EFFECT DEMONSTRATION
of generating nonwords: Implications for semantic-memory interpretations of the generation effect. Journal of Verbal Learning & Verbal Behavior, 21, 243-259. NAIRNE, J. S., PUSEN, C., & WIDNER, R. L., JR.(1985). Representation in the mental lexicon: Implications for theories of the generation effect. Memory & Cognition, 13, 183-19 I. PAYNE, D. G., NEELY, 1. H., & BURNS, D. J. (1986). The generation effect: Further tests of the lexical activation hypothesis. Memory & Cognition, 14,246-252. SCHMIDT, S. R., & CHERRY, K. (1989). The negative generation effect: Delineation of a phenomenon. Memory & Cognition, 17, 359-369. SLAMECKA, N. J., & FEVREISKI, J. (1983). The generation effect when generation fails. Journal of Verbal Learning & Verbal Behavior, 22, 153-163.
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SLAMECKA, N. J., & GRAF, P.(1978). The generation effect: Delineation of a phenomenon. Journal of Experimental Psychology: Human Learning & Memory, 4, 592-604. SLAMECKA, N. J., & KATSAITI, L. T. (1987). The generation effect as an artifact of selective displaced rehearsal. Journal ofMemory & Language, 26, 589-607. THINK PASCAL 4.0 [COMPUTER PROGRAMMING LANGUAGE]. (1991). Cupertino, CA: Symantec Corporation. WATKINS, M. J., & SECHLER, E. S. (1988). Generation effect with an incidental memorization procedure. Journal of Memory & Language, 27,537-544. (Manuscript received November 3,1997; revision accepted for publication April 6, 1998.)
